Short Notes: Three Phase Circuits | Short Notes for Electrical Engineering - Electrical Engineering (EE) PDF Download

Download, print and study this document offline
Please wait while the PDF view is loading
 Page 2


 
 
 
 
 
Negative Sequence (acb) 
??
0
an P
V V 0 
? ? ?
0
cn P
V V 120 
? ? ? ? ?
00
bn P P
V V 240 V 120 
For both phase sequence, 
 ??
an bn cn
V V V 
 
Connections 
Star Connection 
 
 
 
 
 
 
 
 
                                                                                                  
??
?
0
LP
Lp
V 3V 30
II
                             
ab
V = line to line voltage or line voltage 
0
ab an bn P
V V V 3V 30 ? ? ? ?
 
So, line voltage 
ab bc ca
V ,V ,V are 3 times the phase voltage & lead the respective phase voltage 
by 
0
30 . 
Line currents 
a b c
I ,I ,I in this connection are equal to phase currents. 
Phase current are the currents that flow in individual phases. 
 
 
 
Page 3


 
 
 
 
 
Negative Sequence (acb) 
??
0
an P
V V 0 
? ? ?
0
cn P
V V 120 
? ? ? ? ?
00
bn P P
V V 240 V 120 
For both phase sequence, 
 ??
an bn cn
V V V 
 
Connections 
Star Connection 
 
 
 
 
 
 
 
 
                                                                                                  
??
?
0
LP
Lp
V 3V 30
II
                             
ab
V = line to line voltage or line voltage 
0
ab an bn P
V V V 3V 30 ? ? ? ?
 
So, line voltage 
ab bc ca
V ,V ,V are 3 times the phase voltage & lead the respective phase voltage 
by 
0
30 . 
Line currents 
a b c
I ,I ,I in this connection are equal to phase currents. 
Phase current are the currents that flow in individual phases. 
 
 
 
 
 
 
 
 
 
Delta Connection 
 
 
 
   
                                                                                      ?
LP
VV 
                                                                                       
0
LP
I 3I 30 ? ? ? 
 
 
 
 
 
Line current is 3 times phase current & lags respective phase current by 
0
30 . 
 
 
Power in a balanced 3 ?? system 
L L P P
P 3V I cos 3V I cos ? ? ? ? 
L L P P
Q 3V I sin 3V I sin ? ? ? ? 
??
L L P P
**
S 3V I 3V I
 
For power measurement, refer to electrical measurements k-notes, two wattmeter method. 
 
 
 
 
 
 
 
 
 
Read More
69 docs

Top Courses for Electrical Engineering (EE)

Explore Courses for Electrical Engineering (EE) exam

Top Courses for Electrical Engineering (EE)

Signup for Free!
Signup to see your scores go up within 7 days! Learn & Practice with 1000+ FREE Notes, Videos & Tests.
10M+ students study on EduRev
Related Searches

Sample Paper

,

pdf

,

shortcuts and tricks

,

Exam

,

mock tests for examination

,

Short Notes: Three Phase Circuits | Short Notes for Electrical Engineering - Electrical Engineering (EE)

,

Objective type Questions

,

Short Notes: Three Phase Circuits | Short Notes for Electrical Engineering - Electrical Engineering (EE)

,

Important questions

,

study material

,

Viva Questions

,

Semester Notes

,

past year papers

,

Summary

,

Extra Questions

,

ppt

,

Free

,

video lectures

,

Short Notes: Three Phase Circuits | Short Notes for Electrical Engineering - Electrical Engineering (EE)

,

MCQs

,

practice quizzes

,

Previous Year Questions with Solutions

;